Rotary steam-engine



No. 607,922. Patented July 26, |898. C. E fEVANS & 0. E. BARNHART.

BQTARY STEAM ENGINE.

3 Sheeis-Sheel I.

(No Model.)

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NAAM/Mk s Patented July gs, |398. c. E. EvANs & o. E. BARNHART. RUTARY STEAM ENGINE.

(Applxcatlon led May 24, 1897.)

In venian;

Patented July 26, |898. C. E. EVANS & O. E. BARNHART.

ROTARY STEAM ENGINE.

(Applieation med my 24, 1597,) (No Model.) 3 Sheets-Sheet 3.

. WASHINGTON D c view of one of the packing-rings.

CHARLES E. EVANS AND ORRIN BARNHARnoF TnAYEn, KANSAS.

ROTARY STEAM-ENGINE.

SPECIFICATION formingipart of Letters Patent N o. 607,922, dated July 26, 1898. Application led May 24, 1897. Serial Nol 637,932. (No model.)

T0 all wil/0m, t rmty concern: y y

' Be it known that we, CHARLES E. EVANS and ORRIN E. BARNHART, of Thayer, Ncoshocounty, Kansas, have invented certain new and useful Improvements in Rotary Steam-4` Engines, of which the following is a full,clear, 3

and exact description, reference being had to the accompanying drawings, 'forming a part;

The primary object of the invention-is the production of a thoroughly practical engine of this character which may be used with any iiuid as a propelling power or agent.

A further object is to produce a rotary engine of few parts and which is simple, strong, compact, and durable of construction.

. In order that the invention may be fullyy understood, we will proceed to describe it with reference to the accompanying drawings, in which-` Figure 1 represents a central longitudinal section of a rotary engine embodying our invention. Fig. 2 is an interior View of the same with one cylinder-head and packingring removed and with a part in section. Fig. 3 is a detail perspective view of the stationary core or center piece. Fig. 4 is a face Fig.v 5 is a view similar to Fig. 2, except that it discloses a reversible engine, and therefore embodies some new features. Figs. 6 and 7 are detail views illustrating a follower provided with sliding packing-blocks. Fig. S is a view illustrating in perspective one Vof the cavities wherein the ends of the swinging followers operate.

Like reference-numerals designate corresponding parts in all of the figures.

1 designates the cylinder of the engine, provided with the customary end flanges. 2 2 designate the heads or ends of the cylinder, which are bolted to said flanges. One of said cylinder-heads is provided with a tubular extension or hub portion 3, which is j ournaled rotatably in a bearing-standard 4. The other cylinder-head is provided with a short tubular extension 5, and mounted upon the same isA is located within the cylinder. -provide additional support forsaid piece, it

be hereinafter described and,

the cylinder.

a stuiiing-box 6 of any preferred type, in order to pack the joint between said tubular extension 5 and the cylindrical stem 7, upon which it is rotatably mounted, whichI stem in turn is fitted in the standard 8 and is secured from movement therein by means of setscrews 9. Said stem 7 projects through one cylinder-head from the center piece 10, `which In order to is provided also with an oppositely-projecting stem 11, which finds a support in the bearingsleeve 12. Said sleeve is journaled uponthe stem 11 and is secu red within the hub portion 3 by means of set-screwsl, so as to turn with the cylinder upon said stem. In order to pre-r vent any longitudinal movement of the cylinder or center piece, and therefore any change of relation between said parts, we employ collars 14, mounted upon said hub portion 3 and stem. 7 and secured firmly up against the standards 4 and 8 by means of set-screws 15, which impinge upon said hub portion and said stem.

The center piece 10, which is of cylindrical formation and iits snugly in the cylinder, is

cut away at one side, so as to form the substantially abrupt abutment or shoulder 16, which extends, preferably, at an angle to the axis of the cylinder, the oppositely-located rounded shoulder 17 and the concentric surface 18 connecting the bases of said shoulders and extending concentrically to the axis of The `center piece is provided with the passages 19 and 20, which preferably extend through the stem 7 and are connected and communicate, respectively, with steam supply and exhaust pipes, as shown in Fig. 1. At the center of the center piece said passages extend outwardly, and the passage 19 communicates with the steam-distributing chamber 21, provided with a plurality of ports 22, which open into the cylinder through the abutment 16, as shown, while the passage 2O communicates with the opening 23 in the sloping shoulder 17 as an outlet or escape port for the exhaust-steam.

In order to make and maintain a steamtight joint between the faces of the center piece and the cylinder, we employ a pair of packing-rings 24, which lit squarely against the opposite faces of the center piece and en- IOO gage the annular recesses 25, formed in the cylinder, asshown in the drawings. To maintain said rings and the cylinder in their proper relative positions, the former are provided at one or more points with outwardlyprojecting pins 26, which engage correspondingly-located cavities 27 in the cylinder, and thereby prevent any independent rotatable movement of the cylinder or said rings. To prevent any possibility of the steam passing inward between the center piece and said rings, the former is provided concentrically of its axis with an annular groove in each face, and fitting therein snugly are packing-rings 2S, held with a yielding pressure by the springs 29 against the rings 24 in order to automatically compensate for wear, that a perfect joint may always be maintained.

At two or more points equidistant from each other the cylinder is provided with the offsetting chambers 30, preferably of rectangular configuration, and said chambers are rounded at their corresponding ends,as shown at 3l, and at their opposite ends are approximately circular, as shown at 32. 33 designates a corresponding number of followers. These are concaved at their inner sides, as shown at 34, so that they will coincide with and form practically a continuation of the inner surface of the cylinder when occupying their outward or inoperative positions. At one end they terminate in the cylindrical heads 35, which are pivotally yet snugly iitted in the cylindrical cavities 32 in order that said followers may swing back and forth as the engine rotates in a manner to be presently explained.

36 designates segmental cavities which are formed in the inner faces of the packingrings 24 at the opposite ends of the followers. Said segmental cavities are struck from the same centers as the followers and in configuration correspond to the outline described by the space through which said followers swing-that is to say, the outer walls of said cavities coincide, by preference, with the outer surfaces of the followers when they occupy their inoperative positions, and their inner sides are curved, as at 37, so as to coincide with the concave inner sides of said followers when they occupy their operative positions. Said cavities from said outer sides slope gradually inward to their curved inner sides 37,which sides (represented most clearly by the line in Fig. 8) occupy the plane of the inner surface of the packing-rings 24, in order that when said followers swing inward to their operative position they may at their concave edges come into frictional engagement with the packing-rings at the point where the sloping surfaces of the cavities merge into the plane of the inner faces of the packing-rings, as represented most clearly by said curved line 37 in Fig. S. By forming said packing-rings with such cavities it is obvious that the followers may swing through a space outlined by said cavities without frictional contact the curved line 37, representing the junctionpoint of the base of the cavity with the inner surface of the rings, contact between the follower and said rings takes place, and a steamtight joint is established and maintained as Y long as the follower remains in such position, without friction, owing to the fact that when it once assumes this position it continues it, or remains fixed until it instantaneously breaks such contact as it starts to swing outwardto its inoperative position. When it reaches such inoperative position, its outer surface or margin contacts with the corresponding portion of said cavities, and thereby establishes a steam-tight joint at such points, in order that steam in advance of such inoperative follower may not pass backward, and thereby impair the efficiency of the engine, as the pressure of such steam should be entirely utilized in acting upon the preceding follower.

In order to prevent the steam passing back between the uncut portion of the stationary center piece l0 and the cylinder, we provide a longitudinal ,groove 38 in the periphery of said center piece and mount therein the packing-strip 39, which is forced outward with a yielding pressure by the springs 40, arranged in holes drilled or cast in the center piece. (See dotted lines, Fig. 2.) vThe strip is of sufficient width to bridge the spaces or chasms left between the cylinder and the pivoted ends of the followers to permit the latter to operate, and consequently maintains a steamtight connection with the cylinder or the passing follower at all times.

In order to further compensate for wear between the center piece and the packingrings 24, we may employ set-screws arranged at intervals in the cylinder-heads and engaging at their inner ends the cavities 42 of said packing-rings, and these set-screws are prevented from workin g loose by means of checknuts 43. By this arrangement it is obvious that wear between the parts may be easily and quickly compensated for.

With reference particularly to Figs. l and 2 the operation of the engine is as follows: Assuming it to be in the position shown and lthe steam entering by way of the passage 19,

noticed in this connection that the inner side of the follower coincides with the curved line 37 of its respective cavity and that the edge of the follower iits squarely upon the concentric surface 18 of the center piece between the inlet and the outlet ports, and conse- IOO IIO

IZO

-to the fact that the steam-pressure holds the follower frictionally against the center piece as long as it occupies its operative position, that the connection between the follower and the center piece will be perfectly steam-tight.

.In fact, it is what we term an automatic packing, which becomes, if anything, more perfect the longer the engine is used. As the rotation of the cylinder continues the second follower clears the uncut portion of the center piece and drops past the steam-supply ports 22, and at the same instant the preceding follower begins to uncover the exhaustport 23, in order that the steam between said follower and the succeeding one just referred to may escape by way of the passage 20. Immediately said succeeding follower clears the ports 22 the steam enters the chamber 30 and insures the proper and quick downward movement of the follower until at the instant its concave surface Acoincides with` the curved line 37 of its respective cavity its free edge reaches and contacts with the concentric surface 18 at the base'of the abutment 16. The full power of the steam,both its direct and expansive pressure, now fulcrums upon the abutment and exerts its full pressure upon said follower and the cylinder Within the opposing recess 30. This action continues until said follower reaches and uncovers the exhaust-port and the next follower begins to feel the pressure of the steam, all succeeding operations being repetitions of those already described.

It will be understood, of course, that a govv ernor of any suitable or preferred type may be used in connection with this engine, the cylinder alone of which rotates, and to render this more convenient and also to render more convenient the placing of a belt-pulley upon itone of the cylinder-heads is provided with a'tubular extension or hub portion 3, and it should be noticed in this connectionthat this engine can never be run so rapidly that it will rack itself to pieces, owing to the fact that the followers, due to centrifugal action under too high a speed, will swing out from their operative position and permit the steam to escape through the exhaust-ports. This outward swing of course could not take place until the follower' had approximately reached the position shown in Fig. 2, at which time the pressure of the steam is exerted most, per-` haps, upon the squared forward end of the recess 30 of the cylinder proper. In other words, the cylinder would be sustaining at this time mostly direct pressure, while the pressure onthe follower would be lateral alf In order to insure the instantaneous downward movement or response of each follower as it successively clears the abutment that action ofthe steam through the ports 22 may be had as quickly as possible, we have provided the center piece with a series of auxiliary inlet-ports 44, which open out through the periphery of the center piece into the curved end of the cavity 30, so that as the follower in the operation of the engine uncovers said ports the steam may escape therethrough and pass through the narrow recess 45, which at this time affords connection between the curved end and the recess 30 proper above the inoperatively-positioned follower. Immediately this takes place the follower is about ready to clear the free end of the abutment, and by such steam-pressure upon it the downward movement4 of the follower is madeinstantaneous and reliable and overcomes any tendency which the follower may have to maintain its outermost or inoperative position due to centrifugal power.

If desired, the cylinder itself may form the wall for engagement by the power-transmitting belt (not shown) instead of mounting a pulley upon the tubular extension or hub 3,

as hereinbefore suggested. In case the cylinder is employed as a belt-wheel it is obvious that it is preferable to provide each cylinder-head with a stuffing-box, as illustrated upon one of them only in this connection. It is also obvious that instead of conveying the steam in and out through one end of the shaft it may be conveyed into one end and out of the other without departing from the spirit and scope of the invention in the slightest degree. Again, instead of mounting a beltwheel upon the tubular extension or hub 3, or even using the cylinder itself as a beltpulley, we may prefer to clamp a sectional pulley upon the cylinder, and this arrangementundoubtedly will be convenient in many connections, owing to the fact that it will facilitate the placing in position and removal of belt-wheels of varying diameters. This arrangement is illustrated in Fig. 5, the upper section being clamped to the `lower section and both upon thecylinder by means of bolts 46 and clamping-'nuts 47.

In Fig. V5, also, we have modified the construction of the interior ofthe engine in a degree in order to make the same reversible. In carrying out this object the passages 19 and 20 form the inlet and outlet, respectively, accordingly as the engine is rotating in one direction or the other. When it is rotating in the direction indicated by the arrow, same figure, the passage 20 is the 'inlet and the passage 19 the outlet, and when the direction of rotation is reversed the passage 19 becomes the inlet and 2O the outlet of the steam, said passages each terminating in the chambers 21,

the ports 22, and the auxiliary ports 44, and in this case the abutment 16 is duplicated and the sloping` or rounded shoulder 17 is dispensed with by preference. In this case, also, a-duplicate set of followers must be employed, said followers being disposed in opposite di- IOS) IIO

rections and arranged alternately-that is to say, the pivots of the adjacent followers of each set will be close together. A further change to be noted is the employment of springs 48, secured by pins or screws, as at 49, to the cylinder and having their opposite or removable ends secured to the pivoted ends of the followers, as shown or in any other suitable or preferred manner, in order that the tendency of said springs will be to continuously force said followers outward, so as to hold their concave surfaces 34 concentric with the axis of the cylinder, that they may freely pass the abutments of the center piece when the engine is rotating in one direction or the other. These springs, therefore, exert their power in the direction in which centrifugal action would throw said followers. As a consequence the pressure of the steam is necessary to counterbalance the centrifugal action and the action of said springs on those followers which are inoperative when the engine is rotating in one direction, while the steam-pressure assists the centrifugal action and the action of said springs to hold the inoperative followers in their outermost and therefore inoperative positions, in order that there will be no possible chance of their striking the abutment toward which they rotate, and consequently injuring or possibly totally disabling or wrecking the engine. rlhe followers which point or have their free ends disposed in the direction in which the engine rotates in Fig. 5 are the inoperative followers, while the alternatelyarranged and oppositely-disposed followers are the operative ones, as will be readily understood. Owing to the fact that the cylinder or casing of the engine rotates instead of the inner portion, a greater leverage is obtainedl than can be from any rotary engine taking power from an inner rotatable portion of equal diameter or steam capacity. By taking the power at the farthest point possible from the center less steam is needed, and fuel is therefore economized.

By referring now to the modification illustrated in Figs. 6 and 7 it will be observed that we provide the followers with packing-blocks 50 in their ends and hold them with an elastic or expansive pressure continually against the inner faces of the packing-rings 24 of the cylinder, so as to establish and preserve a steam-tight joint. To accomplish this, holes 51 are drilled in the followers and springs 52 arranged therein to exert a continuous outward stress upon the packing-blocks 50. In order to absolutely insure against leakage of steam past the operative follower-wiz., that between the inlet and outlet ports-Weprovide for an auxiliary or intensified pressure on the packing-blocks. This pressure is supplied by the steam, a quantity entering the opening 53 in the rear side (with respect to the direction of rotation) of the follower and expanding outwardly in the communicating passage 54. As this passage is covered at its ends by the packing-blocks the latter are pressed more firmly against the inner surface of the packing-rings 24, and a more perfect joint is the result. The greater friction thus engendered is counterbalanced by the utilization of all the steam-pressure. It will be noticed, too, that this pressure continues on each follower only while it moves from the inlet to the outlet port. In case these pressureactuated packing-blocks are used rings 24 not providedlwith the cavities 36 will be employed, as such cavities would interfere with the proper action of the packing-blocks 50- in fact, would make it verydiflicult, if not impossible, to maintain a steam-tight joint between the followers and the packing-rings.

From the foregoing it will be apparent that we have produced a rotary engine which embodies the features of advantage enumerated in the statement of invention and which combines strength, durability, and inexpensiveness of manufacture in a high degree, and it is to be understood, of course, that various changes may be madein the form, proportion, and detail construction, or mechanical equivalents may be substituted, without departing from the spirit and scope or sacrificing anyof the advantages of our invention.

Having thus described the invention, what we claim as new, and desire to secure by Letters Patent, is

1. A rotary engine, comprising a stationary cylindrical center piece cut away at one side to form abutments or shoulders and provided with inlet and outlet ports, a cylinder fitting snugly but rotatably upon the center piece and provided with cavities in its inner sides, having their bottoms sloping inwardly and merging into the plane of the inner sides of the cylinder on a curved line which intersects the curved surface `of the center piece, and followers hinged to the cylinder and provided with concaved inner vsides,which at times extend concentric to the axis of the cylinder, and at other times coincide and contact with the side walls of the cylinder upon the said curved line representing the junction of said side walls with the inclined bottoms of said cavities, for the purpose set forth.

A rotary engine, comprising a stationary cylindrical center piece cut away at one side to form abutments or shoulders and a concentric surface connecting the bases of said abutments or shoulders, and provided with inlet and outlet ports, a cylinder fitting snugly but rotatably upon the center piece and provided with cavities in its inner sides, having their bottoms sloping inwardly and merging into the plane of the inner sides of the cylinder on a curved line which intersects the curved surface of the center piece, and followers hinged to the cylinder and provided with concaved inner sides which at times extend concentric to the axis of the cylinder and at their outer sides contact and form a steam-tight joint with the inner sides of the cylinder, and at other times coincide and contact with the IOO IIO

side walls of the cylinder upon the said curved line representing the junction of said side walls with the inclined bottoms of said cavities, for the purpose set forth.

3. A rotary engine, comprising a stationary center piece provided with oppositely-projecting stems, and reduced diametrically to form a pair of abutments or shoulders and a connecting concentric surface, and provided also with inlet and outlet ports opening through said abutment and with passages communicating with said ports, a cylinder mounted rotatably upon said stems and inclosing the center piece and provided with recesses in its inner side, followers pivoted to said cylinder and adapted to swing in and out of said recesses once in each revolution of the cylinder, packing-rings surrounding the centerpiece stems, fitting snugly between the cylinder-heads and the center piece,v and provided with pins engaging recesses of the cylinder to prevent any independent rotatable movement, means for adjusting said packing-rings inward, packing-rings mounted in the center CHARLES E. EVANS. ORRIN E. BARNHART.

lVitnesses: L. K. CRANDALL,

C. E. BLoUcH. 

